Benign prostatic hyperplasia (BPH) is the most common non-malignant neoplasm in the aging male. The number of men with lower urinary tract symptoms secondary to BPH, is expected to increase substantially as the population ages. Interest in using complementary and alternative medicines, such as phytotherapy, to prevent and manage health care needs has increased dramatically in recent years. The use of phytotherapy to relieve lower urinary tract symptoms, particularly BPH, has spurred interest in Serenoa repens (Saw palmetto) and Pygeum africanum. Both phytotherapeutic agents are used extensively in this country to relieve symptoms of BPH, but little is known about their mechanism of action, efficacy, safety, or the side effects. Although a number of randomized placebo-controlled trials have been published, all suffer from a variety of shortcomings. A long-term randomized placebo-controlled trial is needed to determine if Serenoa repens or Pygeum africanum prevents clinical progression of BPH. Secondary objectives should include a direct comparison of the two phytotherapeutic agents in their ability to improve the symptoms of BPH, the relationship between prostate size and clinical progression of BPH or regression of symptoms, and the ability of objective diagnostic studies to determine which patients are optimal candidates for phytotherapy. The primary goal of this application is to emphasize the ability of Yale University School of Medicine and Yale New Haven Hospital to successfully implement this protocol so that quality data is obtained to achieve the goals of a final protocol yet to be determined. The advantages of this site include: 1) investigators with recent experience in successfully implementing similar including National Institutes of Health (NIH)-sponsored] protocols; 2) an institution with the necessary infrastructure and experience in participating in large multi-center protocols; 3) the presence of the university in an ethnically and socioeconomically diverse community; and 4) peripheral sites in minority communities, that can facilitate inclusion of the historically underserved. The above characteristics and strategies make the Yale University School of Medicine and the Yale-New Haven Hospital an outstanding candidate for a Clinical Center.